| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an ejector capable of controlling a throttle opening of a nozzle without greatly lowering nozzle efficiency. <P>SOLUTION: When a distal end side of a needle valve 44 is formed into a tapered shape so that cross-sectional area may be reduced toward the distal end side and at least the throttle opening is minimum, the distal end side of the needle valve 44 reaches a fluid flow downstream side from a throat part 41a, and passage cross-sectional area of the throat part 41a and succeeding parts, that is, a nozzle diffuser part 41b is made substantially constant.As a result, substantial coolant passage cross-sectional area S of the nozzle diffuser part 41b is gradually expanded to correspond to the tapered shape of the needle valve 44. Since the loss according to rapid expansion in the throat part 41a and succeeding parts therefore can be suppressed, the throttle opening of the nozzle 41 can be controlled without greatly lowering nozzle efficiency and ejector efficiency. <P>COPYRIGHT: (C)2004,JPO |
